MATHURA -- Two policemen, including a superintendent of police were killed and 12 others were injured as police tried to evict around 3,000 encroachers from a park in Mathura, Uttar Pradesh late on Thursday.

The station house officer of the Farah police station Santosh Yadav and the Superintendent of Police (City) Mathura Mukul Dwivedi were killed when activists of Swadheen Bharat Subhash Sena (SBSS) opened fire at the police party that attempted to evict it from Jawahar Park late on Thursday evening.

According to Mathura police, two bullets hit Station Officer (Farah), Santosh Yadav, who was declared dead on arrival by doctors at Niyati Hospital. SP (City) Mukul Dwivedi, who was placed on ventilator support, succumbed to bullet injuries later, said doctors at the private hospital. Over 100 people, including the city magistrate Ram Araj Yadav, were also injured in the clash that lasted for almost four hours.

According to reports, the encroachers were from a semi-religious sect, who described themselves as "Satyagrahis".

Police and Mathura district authorities were quoted as saying that the agitators had occupied the park in the Jawahar Bagh area for over two years.

Reports said that the police had failed to evict them earlier despite a court issuing orders to do so. The 260-acre park is valued in crores of rupees.

The clashes started as a police team went to the park.

Uttar Pradesh's Director General of Police Javed Ahmed said that there was unprovoked firing from the members of an offshoot of the Jai Gurudev sect. He claimed that heavily armed men from the other side fired at the police and the latter had to resort to a baton charge and tear gas shelling and finally opened fire.

Calling the situation "tense", Ahmed said reinforcements, including senior police officers, are being sent to the area.

The encroachers, who have been on a protest for two years, demand "cancellation of the elections" of the President and Prime Minister of India. They also want that diesel be sold at 60 litres a rupee and petrol at 40 litres a rupee. The existing currency, they also say, should be replaced.

According to police, members of this outfit and another smaller organisation, Swadheen Bharat Subhash Sena, had been staging demonstrations at Jawahar Bagh over the last two-and-a-half years. Among the other demands posted on their Facebook page are: "We demand all records relating to the 'Ruler of the Nation', law and order, and also the document of citizenship (which shows how we are citizens of the nation) to be made public."

So far, police have been able to identify only one of the group's leaders, Ram Vriksha Yadav, but have no further information about him or his associates. The Uttar Pradesh Government has reportedly announced an ex-gratia of Rs.20 lakh each for the families of the martyred policemen.